Optical Synthesis of Large-Amplitude Squeezed Coherent-State Superpositions with Minimal Resources

K Huang (1) , H Le Jeannic (1) , J Ruaudel (1) , V B Verma (2) , M D Shaw (3) , F Marsili (3) , S W Nam (2) , E Wu (4) , H Zeng (4) , Y-C Jeong (1) , R Filip (5) , O Morin (1) , J Laurat (1)

1 LKB (Jussieu) - Laboratoire Kastler Brossel
2 NIST - National Institute of Standards and Technology [Boulder]
3 JPL - Jet Propulsion Laboratory
4 ECNU - East China Normal University [Shangaï]
5 Palacky University Olomouc

We propose and experimentally realize a novel versatile protocol that allows the quantum state engineering of heralded optical coherent-state superpositions. This scheme relies on a two-mode squeezed state, linear mixing, and a n-photon detection. It is optimally using expensive non-Gaussian resources to build up only the key non-Gaussian part of the targeted state. In the experimental case of a two-photon detection based on high-efficiency superconducting nanowire single-photon detectors, the freely propagating state exhibits a 67% fidelity with a squeezed even coherent-state superposition with a size jαj 2 ¼ 3. The demonstrated procedure and the achieved rate will facilitate the use of such superpositions in subsequent protocols, including fundamental tests and optical hybrid quantum information implementations.

Domaines: Physique Quantique [quant-ph]; Optique [physics.optics]

K Huang, H Le Jeannic, J Ruaudel, V B Verma, M D Shaw, et al.. Optical Synthesis of Large-Amplitude Squeezed Coherent-State Superpositions with Minimal Resources. Physical Review Letters, 2015, 115, pp.023602. ⟨10.1103/physrevlett.115.023602⟩. ⟨hal-03271374⟩